This invention relates generally to operational amplifier, and more particularly to an operational amplifier having an improved gain bandwidth product.
In the case of an operational amplifier utilizing single pole compensation, the open loop gain is generally larger at low frequencies and decreases to unity at the unity gain frequency (f.sub.u) at a rate of 20 db per decade. The gain bandwidth product (GBW) for such a single pole slope is the product of frequency (f.sub.1) and the gain (A.sub.1) at f.sub.1 ; i.e. GBW=A.sub.1 f.sub.1. There may be applications, however, where for operation at f.sub.1, a gain greater than A.sub.1 is desired. Merely increasing A.sub.1 would result in a corresponding increase in the unity gain frequency which in turn may cause the amplifier to be unstable in a closed loop unity gain configuration.